Attention: Level 10 will be the lowest level of Trainers that can access this feature. For Trainers levels 10 and below, we encourage you to keep catching Pokémon and exploring the world of Pokémon GO! We have no doubt that you’ll be a level 10 Trainer in no time!
Players can challenge a nearby user to a Trainer Battle by opening the Battle tab which is found in the Nearby menu. This will reveal a Battle Code which the other player must scan (or you can scan his or her Battle code).
You can also take on users not near you, but you must have achieved Best or Ultra Friends status with the user.
You will have to assemble a League of three Pokemon to start a battle. Just like Gym and Raid battles, you have to use your Pokemon’s Fast Attack to build up enough energy to use the more devastating Charge Attack.
Whether you win or lose, you will still earn rewards, including the rare Sinnoh Stone which lets you transform many of your Pokemon to Gen 4.
However, you can only earn the rewards up to three times a day although you can battle as many times as you want to earn medals.
Players are also encouraged to train with AI-controlled team leader Spark, Candela or Blanche which will also net you similar rewards but only once a day.